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Previous studies have reported that glenohumeral internal rotation deficit (GIRD) may increase the risk of throwing-shoulder injuries. The purpose of this study was to analyze the conditions of the throwing shoulder in professional baseball pitchers with GIRD by comparing with those in pitchers without GIRD.In total, 26 male professional baseball pitchers participated in this study. We evaluated passive range of motion (ROM) and isometric muscle strength at internal rotation (IR) and external rotation (ER) at 90° of abduction, as well as the muscle thickness of the supraspinatus (SSP) and infraspinatus (ISP) by ultrasound. The pitchers were divided into 2 groups: those who exhibited a loss of IR of ≥20° in the throwing shoulder (GIRD group) and those who did not (non-GIRD group).In the GIRD group, the total ROM deficit (throwing side - non-throwing side) (P.001), the muscle thickness ratio (throwing to non-throwing) of the SSP and ISP (P = .017 and P = .014, respectively), and the muscle strength ratio (throwing to non-throwing) of ER (P = .028) were significantly lower than those in the non-GIRD group. In contrast, the muscle strength ratio (throwing to non-throwing) of IR was significantly higher in the GIRD group than in the non-GIRD group (P = .0064).We have shown that GIRD has significant correlations with several conditions, such as atrophy of the SSP and ISP, weakness of ER strength, enhancement of IR strength, limitation of total ROM, and throwing side, all of which could be important factors for throwing-shoulder injuries.

Background Coronal shear fractures of the distal humerus are rare injuries, and fragmentation of the capitellum and trochlea with posterior comminution is challenging for surgeons. We retrospectively evaluated the functional outcomes of patients with coronal shear fractures managed with open reduction and internal fixation, focusing on the number of trochlea fragments in Dubberley type 3B fractures. Materials and methods The functional outcomes of 25 patients, including 8 patients with type 3B fractures, with a mean age (and standard deviation) of 57 ± 20 years, were evaluated at a mean follow-up duration of 15 ± 9 months. Type 3B fractures were classified into two groups: those with two trochlea fragments or less group (group A) and those with three or more fragments (group B). Patient outcomes were assessed with clinical and radiographic examination, range of motion, and the Mayo Elbow Performance scale (MEPS). Results Two patients with type 3B in group B experienced nonunion, and two patients with type 3B in group A and 1 patient with type 1B demonstrated avascular necrosis on radiographs. The average MEPS score was 96.3 points (range, 70-100), with 18 excellent, 5 good, and 1 fair results. The average range of motion was 10 ± 8 to 130 ± 12. The MEPS score worsened as Dubberley classification progressed from type 1 to type 3 (98.3 vs. 96.7 vs. 88, P = .014, respectively) and subtypes A to B (97.9 vs. 90, P = .014, respectively). In comparing groups A and B, the MEPS score was significantly worse in group B (93.8 vs. 76.3, P = .006). Conclusion Our open reduction and internal fixation results were largely good, although functional outcomes were diminished as Dubberley classification progressed from type 1 to type 3 and subtype A to B. Type 3B fractures with three trochlea fragments or more in the elderly were the most difficult to treat with open reduction and internal fixation and possibly 1-term total elbow arthroplasty.

Background Limitations of shoulder range of motion (ROM) have been reported to be at high risk for shoulder disorders in baseball players. In this study, we assessed posterior shoulder muscle stiffness using shear wave elastography in baseball players with and without posterior shoulder tightness. Materials and methods In total, 21 college baseball players volunteered to participate in this study. Passive ROMs for shoulder abduction and horizontal adduction were measured using a goniometer. Subsequently, we divided all participants into 2 groups based on the differences between bilateral shoulder ROMs: STIFF+ and STIFF− groups. Thickness and elasticity of the posterior and inferior shoulder muscles were assessed using ultrasound. Results Shoulder abduction ROM on the throwing side was 114.5° ± 5.3° and 131.3° ± 5.7° in the STIFF+ and STIFF− groups, respectively, which was significantly different between the 2 groups (P = .023). Horizontal adduction ROM on the throwing side was 96.6° ± 4.9° and 110.9° ± 4.8° in the STIFF+ and STIFF− groups, respectively, which was also significantly different between the 2 groups (P = .014). The elasticity of infraspinatus and lower trapezius in the STIFF+ group was significantly greater than that in the STIFF− group (P = .018 and .033, respectively). Discussion In this study, we found that the elasticity of infraspinatus and lower trapezius in stiff shoulders was significantly greater than that in nonstiff shoulders, which indicated that the infraspinatus and lower trapezius could be the key muscles in posterior shoulder tightness.

Introduction Excellent outcomes of arthroscopic rotator cuff repair for small and medium tears have been recently reported. However, re-tears after surgery have been a common complication after surgical repair of large and massive rotator cuff tears and often occur in early postoperative phase. It was previously reported that basic fibroblast growth factor and platelet-rich plasma enhanced rotator cuff tear healing. We hypothesized that this combined therapy could enhance rotator cuff healing after rotator cuff repair in a rat model. This study aimed to evaluate the efficacy of combined therapy of platelet-rich plasma and basic fibroblast growth factor with gelatin-hydrogel sheet. Methods To create a rotator cuff defect, the infraspinatus tendon of Sprague Dawley rat was resected from the greater tuberosity. The infraspinatus tendons were repaired and covered with gelatin-hydrogel sheet impregnated with PBS (control group), basic fibroblast growth factor (bFGF group), platelet-rich plasma (PRP group), or both basic fibroblast growth factor and platelet-rich plasma (combined group). Histological examinations were conducted using hematoxylin and eosin, safranin O, and immunofluorescence staining, such as Isolectin B4, type II collagen at 2 weeks postoperatively. For mechanical analysis, ultimate failure load of the tendon-humeral head complex was evaluated at 6 weeks postoperatively. Results In the hematoxylin and eosin staining, the tendon maturing score of the combined group was higher than that of the control group at postoperative 2 weeks. In the safranin O staining, stronger proteoglycan staining was observed in the combined group compared with the other groups at postoperative 2 weeks. Vascular staining with isolectin B4 in 3 treatment groups was significantly higher than that in the control group. Type II collagen expression in the combined group was significantly higher than those in the other groups. The ultimate failure load of the combined group was significantly higher than that of the control group. Conclusion Combined therapy of basic fibroblast growth factor and platelet-rich plasma promoted angiogenesis, tendon maturing and fibrocartilage regeneration at the enthesis, which could enhance the mechanical strength. It was suggested that combined basic fibroblast growth factor and platelet-rich plasma might enhance both tendon and bone–tendon junction healing, and basic fibroblast growth factor and platelet-rich plasma might be synergistic.

Background Dehydroepiandrosterone (DHEA), an adrenal steroid, has a protective role against diabetes. This study aimed to investigate the in vitro and in vivo protective effects of DHEA against high glucose-induced oxidative stress in tenocytes and tendons. Methods Tenocytes from normal Sprague-Dawley rats were cultured in low-glucose (LG) or high-glucose (HG) medium with or without DHEA. The experimental groups were: control group (LG without DHEA), LG with DHEA, HG without DHEA, and HG with DHEA. Reactive oxygen species (ROS) production, apoptosis, and messenger RNA (mRNA) expression of NADPH oxidase (NOX) 1 and 4, and interleukin-6 (IL-6) were determined. Further, diabetic rats were divided into a control group and a DHEA-injected group (DHEA group). NOX1 and NOX4 protein expression and mRNA expression of NOX1, NOX4, IL-6, matrix metalloproteinase (MMP)-2, tissue inhibitors of matrix metalloproteinase (TIMP)-2, and type I and III collagens in the Achilles tendon were determined. Results In rat tenocytes, DHEA decreased the expression of NOX1 and IL-6, ROS accumulation, and apoptotic cells. In the diabetic rat Achilles tendon, NOX1 protein expression and mRNA expression of NOX1, IL-6, MMP-2, TIMP-2, and type III collagen were significantly lower while type I collagen expression was significantly higher in the DHEA group than in the control group. Conclusions DHEA showed antioxidant and anti-inflammatory effects both in vitro and in vivo. Moreover, DHEA improved tendon matrix synthesis and turnover, which are affected by hyperglycemic conditions. DHEA is a potential preventive drug for diabetic tendinopathy.

Background Most rotator cuff tears are the result of age-related degenerative changes, but the mechanisms underlying these changes have not been reported. Recently, advanced glycation end products (AGEs) have been regarded as an important factor in senescence. Therefore, we hypothesized that AGEs would have detrimental effects on rotator cuff–derived cells. In this study, we investigated the influence of AGEs on rotator cuff–derived cells in vitro and ex vivo. Methods Rotator cuff–derived cells were obtained from human supraspinatus tendons. The cells were cultured in the following media: (1) regular medium with 500 μg/mL AGEs (High-AGEs), (2) regular medium with 100 μg/mL AGEs (Low-AGEs), and (3) regular medium alone (Control). Cell viability, secretion of vascular endothelial growth factor, and the expressions of hypoxia-inducible factor-1α, reactive oxygen species, and apoptosis were assessed after cultivation. An ex vivo tissue culture with AGEs was also performed to measure the tensile strength. Results Cell viability in the High-AGEs group was significantly suppressed relative to that in the Controls. The amount of vascular endothelial growth factor secretion was significantly greater in the High- and Low-AGEs groups than in the Controls. Immunofluorescence stain demonstrated enhancement of hypoxia-inducible factor-1α and reactive oxygen species expressions and cell apoptosis in the High- and Low-AGEs groups relative to that in the Controls. In ex vivo mechanical testing, tensile strength was significantly higher in the Control group than in the AGEs groups. Discussion These results indicated that AGEs caused age-related degenerative rotator cuff changes. The reduction of AGEs might prevent rotator cuff senescence-related degeneration.

Olecranon apophyseal nonunion is an elbow injury from overuse that affects adolescent athletes such as baseball pitchers who participate in overhead throwing sports. However, such injury is rare in collision sports. Here, we report two patients with this condition who are Judo athletes. The purpose of this report was to describe three elbows with olecranon apophyseal nonunion in two adolescent patients participating in Judo. This is a case series; the level of evidence is 4. Two 15-year-old patients were evaluated. One suffered from unilateral and the other from bilateral chronic posterior elbow pain. They were diagnosed with olecranon apophyseal nonunion, which was treated using internal fixation and bone grafting. Radiographic evidence of the apophyseal union was observed four months postsurgery. Two elbows were treated with tension band wiring, then they underwent hardware removal six months postsurgery. Both patients returned to their previous levels of activities six months postsurgery. Internal fixation using autologous bone grafting was a useful treatment for these Judo athletes with olecranon apophyseal nonunion.

Introduction The superficial branch of the radial nerve (SBRN) has a risk of nerve injury during cephalic vein (CV) cannulation. Due to the lack of imaging study regarding SBRN and CV relationship, we analyzed the anatomical relationship between the SBRN and the CV using ultrasound (US) imaging. Materials and Methods In total, 82 upper limbs of 41 healthy volunteers were analyzed. The SBRN and CV were identified at the following three points in the elbow extension and pronation position: at the radial styloid process (point 1), 5 cm proximal to point 1 (point 2), and 10 cm proximal to point 1 (point 3). Results The distance between the SBRN and CV was 1.1 ± 1.0 mm at point 1, 1.3 ± 1.3 mm at point 2, and 2.1 ± 1.6 mm at point 3. The depth of the SBRN from the surface of the skin was 2.7 ± 0.9 mm at point 1, 3.5 ± 1.1 mm at point 2, and 5.5 ± 1.9 mm at point 3. The percentage of the SBRN that ran beneath the CV was 17.5%, 53.5%, and 92.4% at points 1, 2, and 3, respectively. Conclusion Ultrasonography can reveal the anatomical relationship between the SBRN and CV.

When constructing networks or changing network designs, workers follow procedure manuals to issue commands to network devices. Procedure manuals are usually created manually, and may include mistakes. We therefore extend Graphical Network Simulator 3 for supporting creation of procedure manuals for network device configurations. In our system, users first use a virtual network to construct a target network, then verify the network using a verification function. Users then produce manuals from a procedure-manual creation function. Using our system, procedure manuals can be created while suppressing human errors and variation in user experience. Experimental evaluations confirm that procedure manuals created by our system can be used for configuring network devices.

Background: Improvements in ultrasound diagnostic equipment and techniques can enable muscle stiffness to be measured quantitatively as muscle elasticity using ultrasound shear wave elastography (USWE), where high muscle elasticity values represent muscle stiffness. Purpose: To use USWE to analyze the sequential changes in muscle elasticity in the posterior shoulder before and after pitching. Study Design: Descriptive laboratory study. Methods: The authors evaluated 14 baseball players who had played in high school or college at an intermediate level. The elasticity of the supraspinatus, infraspinatus (ISP), middle trapezius, lower trapezius (LT), rhomboideus, and serratus anterior muscles of the throwing shoulder was measured using USWE at 3 time points: before, immediately after, and 24 hours after a throwing session of 100 pitches. The authors analyzed the sequential changes in the mean elasticity values of the respective muscles at the 3 time points. Results: The mean elasticity values before, immediately after, and 24 hours after throwing were as follows: supraspinatus: 32.9, 53.4, 43.8 kPa; ISP: 22.7, 44.8, 43.7 kPa; middle trapezius: 45.1, 70.3, 59.9 kPa; LT: 32.8, 45.5, 46.5 kPa; rhomboideus: 29.1, 47.5, 38.8 kPa; and serratus anterior: 19.2, 36.9, 26.5 kPa, respectively. The mean elasticity values for all tested muscles were significantly higher immediately after throwing compared with before throwing ( P ≤ .0086 for all), and elasticity values in the ISP and LT remained significantly higher 24 hours after throwing compared with before throwing ( P ≤ .019 for both). Conclusion: The study results indicated that pitching significantly increased ISP and LT muscle elasticity even after 24 hours.

Triangular Fibrocartilage Complex (TFCC) improves stability of the wrist joint. TFCC injures occur due to falling, traffic accident, abuse of wrist at work, long-time sport such as tennis, baseball and so on. A method of treatment of TFCC injuries is almost established. However, diagnosis has many points to be improved. There are imaging and palpation for diagnosing TFCC injuries. Imaging can confirm ligament tear; however, it cannot measure bone movement. On the other hand, there are ballottement test, piano key sign, ulnar fovea sign and so on in palpation methods, but these methods largely depend on doctor's sense and experience. Therefore, it is impossible to diagnose quantitatively yet. This study has developed a measurement system to assess instability of ulna toward palmar side and wrist pressure quantitively in real time by using 3D electromagnetic sensor and pressure sensor. Then, this study has measured instability of healthy people. After that, we analyzed a strain of the measurement. In addition, we confirm the repeatability of strain in healthy people.

Background During throwing, the force generated by the lower extremities is transferred through the core, shoulder, elbow, and ultimately, the hand before ball release via the kinetic chain. Therefore, an insufficient hip rotation range of motion (ROM) can arrest the throwing mechanics. Recently, we developed a new scoring system of hip stiffness (Hip Stiffness Score; HSS) for medical assessment of baseball players. In this study, we investigated the correlation between HSS and shoulder conditions in the baseball pitchers. Materials and methods Twenty-seven professional baseball pitchers volunteered for this study. HSS to quantitatively evaluate hip stiffness includes 4 physiologic parameters, including 1 straight leg raising (SLR) test, 2 hip internal rotation (HIR), 3 adduction, and 4 heel buttock distance (HBD). Bilateral glenohumeral internal and external-rotation (IR and ER) ROM were also measured passively, and IR and ER strength of shoulder were assessed bilaterally. In the ultrasound assessments, all participants were scanned by using an Aplio™500 to assess the muscle thickness of supraspinatus (SSP) and infraspinatus (ISP). Results HSS showed a mild positive correlation with total arc of motion (TAM), weak positive correlations with glenohumeral internal rotation deficit (GIRD) and glenohumeral external rotation gain (GERG), and weak negative correlations with IR and ER strength. Then, the participants were divided into 2 groups according to HSS; more than 3 points of HSS was regarded as a high HSS group (n = 12), and less than 2 points as a low HSS group (n = 15). The GERG in the high HSS group was significantly greater than that in the low HSS (p Discussion HSS has some correlations with TAM, GIRD, GERG, IR and ER strength of shoulder. It is assumed that the insufficient hip ROMs could inhibit the kinetic chain in throwing motion. Furthermore, the pitchers with the higher HSS showed greater GERG and lower ER strength. The increase of GERG and decrease of ER strength were reported to lead to shoulder and elbow injuries. Therefore, it is possible that the HSS could be useful for the medical check-up of the pitchers.

Background Excellent clinical results of arthroscopic surgical repair have been reported for rotator cuff tears, however treatment of large and massive rotator cuff tears remains challenging. We have performed single row repairs with graft augmentation of fascia lata for large and massive rotator cuff tears in order to reduce a tension at the tendon-bone repair site for prevention from retear of the repaired rotator cuff. The purpose of this study was to evaluate clinical outcomes and rotator cuff integrity after arthroscopic rotator cuff repair (ARCR) with graft augmentation of the fascia lata. Material and methods Nineteen patients who underwent ARCR but unable to perform footprint fixation were included. These patients (14 males and 5 females), with an average age of 66.2 years old (range; 52–79 year old), were diagnosed with a large and massive rotator cuff tear. Single row repairs with footprint medialization were performed in 7 cases (SR group) and graft augmentation of fascia lata in addition to single row repairs were done in 12 cases (GA group). MRI was assessed at 6 and 12 months postoperatively and a retear was defined as discontinuity of the repaired supraspinatus tendon. Japanese Orthopaedic Association (JOA) score, UCLA score, and Constant score were assessed as clinical outcomes. Results MRI examinations revealed 6 retears out of 7 SR cases (re-tear rate: 85%) and 2 cases out of 12 GA cases (re-tear rate: 17%) at 6 months postoperatively. There was no additional retear at 12 months. JOA score, UCLA score, and Constant score in both groups significantly improved at the final follow-up, but there was no statistical difference between both groups on each score. The abduction strength significantly improved only in the GA group. Discussion In the present study, ARCR with graft augmentation of fascia lata for large and massive rotator cuff tears showed good clinical scores with a low retear rate and improvement of abduction strength. The low retear rate might be due to reduction of tension at the cuff repair site. Therefore, graft augmentation of fascia lata would be a useful option for large and massive rotator cuff tears.

Background Fascia lata augmentation of massive rotator cuff tears has shown good clinical results. However, its biological effect during the early healing process is not clearly understood. The purpose of the study was to evaluate the biological efficacy of fascia lata augmentation during the early healing process of rotator cuff tears using a rabbit rotator cuff defect model. Methods The infraspinatus tendon was resected from the greater tuberosity of a rabbit to create a rotator cuff tear. The tendon edge was directly sutured to the humeral head. The rotator cuff repaired site was augmented with a fascia lata autograft (augmentation group, group A). The rotator cuff defect in the contralateral shoulder was repaired without augmentation (reattachment group, group R). A group with intact rotator cuff was set as the control group. Histological examinations and mechanical analysis were conducted 4 and 8 weeks postoperatively. Results In the HE staining, the tendon maturing score of group A was higher than that of group R at 4 weeks postoperatively. In the safranin O staining, proteoglycan staining at the repaired enthesis in group A at 4 weeks postoperatively was stronger than that in group R. Picrosirius red staining showed that type III and type I collagen in group A was more strongly expressed than that in group R at 4 weeks postoperatively. The ultimate failure load of the infraspinatus tendon–humeral head complex in group A was statistically higher than that in group R at 4 weeks postoperatively. The ultimate failure load of group A was similar to that of the control group. Conclusion The biological and mechanical contribution of fascia lata augmentation for massive rotator cuff tears was analyzed in this study. Type III collagen was reported to be expressed during the tendon healing process. Although the biological action similar to natural ligament healing occurred around the fascia lata grafts, type III collagen was gradually replaced by type I collagen as the tissue matured. Our results suggest that fascia lata augmentation could stimulate biological healing and provide initial fixation strength of the repaired rotator cuff.

Background Aging impairs tendon healing and is a potential risk factor for chronic tendinitis. During normal aging, tendons undergo structural and biomechanical degenerative changes, accompanied by a reduction in the number of tenocytes and changes to their properties. However, molecular changes in aged tendons under inflammatory conditions are not well understood. The present study analyzed the molecular changes in collagenase induced acute tendon injury using a senescence-accelerated mouse (SAM) model. Methods SAMP6 mice were used as an aging animal model and SAMR1 mice were used as a control to represent a senescence-resistant inbred strain. All the mice used in the study were 40 weeks old. Collagenase I from Clostridium histolyticum (20 μL) was injected percutaneously to the tendon-bone junction of the Achilles tendon. Two weeks after treatment, the Achilles tendons were harvested and stained using Picrosirius Red to determine collagen expression. Real-time PCR was performed to analyze gene expression of IL-6, tenomodulin, type I and type II collagen, MMP-9, TIMP-1, and TIMP-2. Results Collagenase injection resulted in significantly higher gene expression of IL-6 but significantly lower tenomodulin expression compared with the control in SAMP6 and SAMR1 mice. In SAMP6 mice, gene expression of type III collagen and MMP-9 was significantly higher in the collagenase-injected group compared with the control group. SAMP6 mice also showed lower expression of type I collagen, TIMP-1, and TIMP-2 in the collagenase-injected group compared with the control group. Picrosirius Red staining showed the highest expression of type III collagen in the collagenase-injected SAMP6 group compared with the other groups. Conclusions The collagenase-injected SAMP6 group showed higher expression of IL-6, MMP-9, and type III collagen and lower expression of type I collagen, TIMP-1, and TIMP-2, which are known to suppress metalloproteinases. The results indicate that aging may lead to dysfunction of the tendon healing process after acute tendon injury.